What are the limitations of voip?

You can put a lock on it and then forget the code to unlock it. That's what I did. Also, with a voicemail system, you cannot listen to the beginning of an incoming message and decide to pick up the phone and speak to the caller directly, as you can with an answering machine.

Voice mail service is more of advantages than disadvantages because the service is always present to accept unattended phone calls leaving you with no missed calls.